Usage in various languages

Afrikaans

In Afrikaans, the trema (Afrikaans: deelteken) is mostly used to indicate that the vowel should not be diphthongised, for example geër ("giver") is pronounced [χeər], whilst geer (a wedge-shaped piece of fabric) is pronounced [χiːr]. There are some cases where the deelteken does nothing to the pronunciation, like in reën ("rain"), which is pronounced [reən], but reen (no meaning) would be pronounced the same. The only reason for the deelteken in this case is for traditional reasons, because the archaic form of reën is regen and the deelteken just indicates that the g was removed. Some older people do pronounce reën in two syllables ([ˈreː.ən]).

The deelteken does exactly what it says (deelteken being Afrikaans for "separation mark"). It separates syllables, as it indicates the start of a new one. An example of this is the word voël ("bird"). It gets pronounced in two syllables. Without it the word becomes voel ("feel"), pronounced in one syllable.

Albanian

Ë is the 8th letter of the Albanian alphabet and represents the vowel /ə/. It is the most commonly used letter of the language comprising 10 percent of all writings.

Ascolano

Ë is a phonetic symbol also used in the transcription of Abruzzese dialects, especially in its northern variant in the Province of Ascoli Piceno and it's called "mute E": sounds like an é but just hummed. It's important for the prosody of the dialect itself.

English

Use of the character Ë in the English language is relatively rare. Some publications, such as the American magazine The New Yorker, use it more often than others.[1] It is used to indicate that the e is to be pronounced: separately from the preceding vowel (e.g. in the word "reëntry", the girl's name "Chloë" or in the boy's name "Raphaël"), or at all - like in the name of the Brontë sisters, where without diaeresis the final e would be mute.

French and Dutch

Ë appears in words like French Noël and Dutch koloniën. This so-called trema is used to indicate that the vowel should not be diphthonged. For example, Noël is pronounced [nɔɛl], whilst Noel would be pronounced [nœl]. Likewise, "koloniën" is pronounced [koːˈloːniən], whilst "kolonien" would be pronounced [koːˈloːnin].

Kashubian

Ladin

Although not used in standard Ladin, Ë is used in some local dialects. It represents /ɜ/.

Latin

In many editions of Latin texts, the diaeresis is used to indicate that ae and oe form a hiatus, not a diphthong (in the Classical pronunciation) or a monophthong (in traditional pronunciations). Examples: aër "air", poëta "poet", coërcere "to coerce".

Luxembourgish

In Luxembourgish, ⟨ë⟩ is used for stressed schwa/ə/ like in the word ëmmer ("always"). It is also used to indicate a morphological plural ending after two ⟨ee⟩ such as in eeër ("eggs") or leeën ("lay").

Mayan languages

In the modern orthography of Mayan languages, the letter Ë represents /ə/, as in Albanian.

Russian

In some Latin transliterations of Russian, Ë is used to represent its homoglyph, representing a stressed /jo/, as in Potëmkin to render the Cyrillic Потёмкин.